Inclosed switch construction



Sept 10, 1929- H. J. HAMMr-:RLY 1,727,767

ENCLOSED SWITCH CONSTRUCTION Filed 051;. 8, 1928 2 sheets-sheet 1 Sept. 10, 1929." H, .1. HAMMERLY ENCLOSED SWITCH CONSTRUCTION Filed Oct. 8, 1928 l2 Sheets-Sheet 2 Patented Sept, 10, 1929.

, UNiTED STATES PATENT OFFICE.

HERMAN J. HAMMERILY, F 'WALLINGFORD, CONNECTICUT, MSIGNOBLTO THETBUM- BULL ELECTRIC MANUFACTURINGCOMPANY, OF PLAINVILI'LE, CONNECTICUT, A.

CORPORATION QF CONNECTICUT.

i l iiTcLosEi) SWITCH CONSTRUCTION.

'-App1ication led October 8, 1928. Serial No. 311,067.

-My invention relates to the class of inclosed switches which are mounted in a box having a cover which may be'locked or .sealed closed to prevent unauthorized access to the switch perse or its terminals and an auxiliary interlocking shutter door carried by the cover,V which-door may be readily A opened by the current consumer to permit manipulation of the fuses when the switch is positively locked .in the off position but which door .j is automatically locked against opening. movement while the switch is in the on position.

I am aware that a number of patents have 15 beenissued on switch' constructions in which the' aboveenumerated safety features have been incorporated ina more or less practical mannerbut many' of the constructions shown are open to objections' fromtlie com` 2o mercal or practical'standpoint. A n

My presentinvention obviates man `of the. objections which are. obvious 1n a-s owing of the prior art.`

. One object of my invention is to rovide -cluding a satisfactory sliding shutter fuse door as distinguished vfroma, hinged or pivoted fuse door or the equivalent. A

Another object is to provide a safety switch construction with a sliding shutter fuse door together with an interlocking bar which projects outside of the box in such a manner as to indicate clearly whether orv not the fuse door is interlocked as well as where and just how it is interlocked with the operating handle.

Another object is to provide an interlocking fuse door construction in which none of the co-related parts are hinged or pivoted.

Another object is to provide an interlocking fuse door construction in which all small parts such as latches, connecting' levers, springs, rivets, etc. are entirely eliminated and the interlocking functions are accomplished positively and solely by the interengagement of the major elements in the normal operation of the switch.

Another object is to provide a safety switch construction having a sliding shutter fuse door so co-ielated with the operating an inclosed safety switch construction in-` 'The switch construction' may be of any practical; these requirements are met by the construction herein disclosed. 60A i.l The drawings show the preferred 'form of construction embodying my invention.

IFig. 1 is a perspective View of aninclosed switch showing the slide open to permit replacement of the fuses and showing the interlock holding the operating handle in the operi circuit position. l

F ig. 2 is a transverse horizontal section of the `construction with the slide closed.l Fig. 3'vis a front view showing the box open.

'Fig f4 is a detailed view of parts of the cover and slide and interlocking members. The box 6 has a cover-7 which may be hinged to it-in the usual manner and which may be provided with a spring catch 8 whereby the cover may be latched or locked in the closed position.

suitable type. The insulating base 10 is supported by brackets 11 and carries stationary contact jaws 12. The removable switch blades 13 are lcarried by an insulating cross bar 14 which is supported by connected rods 15 which` extend through the base. The operating crank 16 is'pivotally supported in the box and engages the connector rods 15 and is provided with an external operating handle 17 adapted to rotate and swing along the side of one wall of the box. The strap or bracket 18 serves as a guard for the handle and also as a means for locking or sealing the handle in either the open oi closed circuit position.

The fuses 2O are detachably mounted in any suitable manner within a receptacle 21 having side walls, the outer edges of which extend close to the inner surface of the cover.

vThe cover is provided 'with an opening 22 100 through which access may be had to the fuse chamber.

A slide 23, supported in guideways 24vat'- `tached tothe inside of 'the cover, normally covers the opening 22. The handle 24: serves asa means for operating the slide as well as a s top to limit the movement of the slide. The interlocking member 25 is preferably formed of heavy wire or rod and has two arms or branches 26 and 27 which are guided in suitable openings in the` flange 28 of the cover. The longer arm 27 is also guided in an'opening in a braeketor flange 29 secured to the cover near one of the guideways. To the inner faee'of the slide 23 is secured a grooved or channel-like guide Inember secured, for instance, by welding or riveting-'The inner end of the interlo'cker rod 27 is bent over at an abrupt angle to forma projection 31 adapted to slide in the 'channelmember 30. Obviously the interlocking member 25 may be made of sheet or cast metal if so desire Gbviously, the angular relation of the .interlocker member 25.` the slide 23 and the guide channel 30 together'with the relatively straight movement .of the slide, will'cause a transversemovement of the interlocker member v25 when the slide is moved upor down so that whenthe switch box is closed and the switch is -in the closed circuit position, the handle 17 stands directly in the path of movement of the projecting outer end of the interlocking memberv 25.. When the switch is open, however, andthe handle in the position shown in ;Fig. 1, the slide 23 may be 'moved downwardly to the position shown.- The engagement of the inclined channel 30 with 'the inner en'd 31 of the interlock 25,

causes the interlock to move outwardly into the path of movement of the handle 17 as shown inFig. 1, so that the switch can not be operated when the fuse compartment is open. It vwill be understoodof course that when the cover is open, the switch may be operated Without any interference of the interlock.

The parts are all simple and so proportioned and arranged as to provide a maximum strength and solidity with a minimum weight of material.

The handle engaging portion of the interlock bar 25 .is exposed at all times so that its relation to the handle is apparent at a'glance. There is therefore no damage dueto the operator unwittingly straining or injuring the parts in a legitimate attempt to operate the switch when the slide is open or to operate the4 slide when the vswitch is closed.

The angular relation of the interlocking parts is such thatthe slide 23 will stay open or closed or in an intermediate position without the use of springs, catches or friction devices.

I It will lbe apparent. from the foregoing that the objects of this invention have been accomplished in a very practical manner with a minimum number of single parts and that the construction is of a very rugged and substantial character.

I claim:

-l. A safety lswitch including a box havingA a cover, a movable 'switch member mounted in said box and having an operating handle outside of said box, said cover having an opening, a slide for closing said opening, a

wire handle obstructing stop guided inside, oi the cover in line with the handle and an in clined guide connected to said slide and having operable engagement with said stop to move said stop in a transverse direction when said 'slide ismoved.

2. A safety switch including a box having a flanged cover hinged thereto, a movable switch member 'mounted in said box and hav.

said opening, a switch mounted in the box and having an external operating handle and a handlelatching rod supported to slide lin a flange of the cover and having one end slidably connected with said-slide and the other end adapted to coaet with said handle, at the edge of the cover when the cover is closed.

4. A safety switch including a box having a cover hinged thereto, a switch mounted in saidbox and having a swinging operating handle outside of'said box, said cover hav ing 'an opening, a slide for closing said opening, a handle stop guided in the cover in line with the handle, an inclined guide connected to said slide and having operable engagement with said stop to actuate said stop, 'and a strap secured to said -box and extending around said handle adjacent ythe outer end of the stop rod.

Y HERMAN J. HAMMERLY. 

